Tandem propeller propulsion and control system



Dec. 13, 1966 F. R. HASELTON TANDEM PROPELLER PROPULSION AND CONTROL SYSTEM 2 Sheets-Sheet 1 Filed March 1 1965 INVENTOR. Frederick R. HaseHon Attorney Dec. 13, 1966 F. R. HASELTON TANDEM PROPELLER PROPULSION AND CONTROL SYSTEM Filed March 1'7, 1965 2 Sheets-Sheet lnvemor Frederick R. HoseHon ATrorney United States Patent 3,291,086 TANDEM PRGRELLER PROPULSION AND CONTROL SYSTEM Frederick R. Haselton, 6001 Johnson Ave., Bethesda, Md. Filed Mar. 17, 1965, Ser. No. 440,648 8 Claims. (Cl. 114-16) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to a propulsion system for a submersible vessel and more particularly to the tandem propeller type of submersible having substantially neutral bouyancy.

A successful type of tandem propeller submersible is shown in my Patent No. 3,101,066, entitled Submarine Hydrodynamic Control System. Such a system is designed for a particular type of deep submersible vessel and is eminently successful therefore. However, it is desirable to improve the maneuverability and the mobility of such vessels. It is difiicult to obtain maneuverability and mobility for a given hull design without compromising the efiiciency of overall operations.

The term spheroid is defined geometrically as a figure generated by the rotation of an ellipse about either its minor or major axis. If the rotation is about the minor axis it is called an oblate spheroid and if it is about its major axis it is called prolate spheriod. It is obvious that when the minor and major axis are equal a sphere is generated. It has been found in designing certain submersibles that the utilization of a spheroid geometry for the outer hull is desirable. Various problems encountered in deep submersion require diiferent constructions and shapes of the pressure hull and generally the outer hull may be defined by an L/ D ratio. A prolate spheroid having a L/ D of 7, approximates a good shape for the more conventional submarine such as the Albacore. On the other hand an L/D ratio of 1/3 would make the submarine a saucer vehicle.

It is the purpose of this invention to provide means, including tandem propellers, to optimize maneuverability and mobility for a varety of spheroid shaped hull designs.

The tandem propeller hubs generally are spaced from the center of the vessel or spheroid hull and are arranged so that their axes are coincident with the axis of the spheroid upon which it is generated and their outer surfaces form a smooth continuation of the hull. In the disclosure presented herewith, and in every case, the spindle holding the blades are oriented such that their axes are normal to the surface of the hub and the hull.

It is an object of this invention to provide an improved tandem propeller construction for a submarine.

It is a further object of this invention to provide a tan-- dem propeller drive system for a submersible wherein the blade spindles are oriented normal to the surface of the hull.

It is yet a further object of this invention to provide a spheroid submersible hull having mounted thereon two equally spaced propeller hubs having a plurality of spindles and blades wherein the orientation of the spindles is such that they are normal to the surface of the submersible hull at all times.

It is still a further object of this invention to provide in a tandem propeller submersible means for continuously and individually controlling the pitch of the various blades; to impart six independent degrees of freedom of motion to the submersible.

Yet another object of this invention is to provide a spheroid submersible hull having mounted thereon at least two spaced propeller hubs having a plurality of spindles 3,29l,8ti Patented Dec. 13, 1966 and blades wherein the axis of the spindles is such that they are normal to the surface of the submersible hull; wherein the spindles are individually rotatable and rotatable as a group.

Still another object of the invention is to provide a pitch control means for a tandem propeller having a plurality of pitch controllable blades wherein the pitch control is provided by a pair of rotatable eccentric and individual control arms to individual spindles.

Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:

FIGURE 1 shows a prolate spheroid type of hull having positioned thereon three typical locations of pairs of tandem propeller hubs and blades;

FIGURE 2 is an oblate spheroid hull having pairs of propeller hubs thereon in three typical locations;

FIGURES 3, 4, and 5 show various positions of propeller hubs and drive means;

FIGURES 6 and 7 are two views of the drive nut on the spindles;

FIGURE 8 is a View along lines 88 in FIGURE 4;

FIGURE 9 is a sectional view through a prolate spheroid outer hull construction of a deep submersible;

FIGURE 10 is a detailed sectional view between lines 10-10 and 10a-10a in FIGURE 9; and

FIGURE 11 is a sectional-view along lines 1111 in FIGURE 10.

FIGURE 1 shows a submersible hull 20 generated by rotating an ellipse about its major axis 21. Shown on hull 20 are three pairs of propeller hubs 22a, 22b, 23a, 23b, and 24a, 24b, any pair being representative of a typical installation, any set of blades may be shrouded as shown in 23a and 23b. It should be noted that in the tandem hub drive type of construction there is counter rotation between the two hubs, thus, applying balanced roll moments to the submersible when the rotation speeds are equal.

FIGURE 2 shows a hull 30 generated by rotating an ellipse about its minor axis 31, resulting in a saucer type submersible. Three pairs of tandem propeller hubs are shown 32a, 32b, 33a, 33b, and 34a, 3412, any pair of which form a typical installation, any set of blades may be shrouded as shown in 3401 and 34b.

In both FIGURES l and 2 a plurality of blades are shown on the individual hubs which provide mobility and maneuverability to the submersibles.

FIGURES 3, 4, and 5 are somewhat schematic detailed presentations of the blade mounting and drive means for producing the necessary driving forces. In each instance a yoke 40 is provided to confine therein for rotational motion a spindle 41 having a blade 42 afiixed thereto. The U shaped yoke member 40 as hereinafter referred to is the hub, and is provided with a driving arm 43. The spindles 41 are rotatable and held in the hub 40 through suitable bearing surfaces, not shown, and in addition have long lead threads thereon which are engaged with a driving nut 44. A control surface 45 has a slot 46, shown in more detail in FIGURE 8 for engaging drive nut 44, shown in detail in FIGURES 6 and 7. With the construction as shown, the drive nut is confined against rotation by its straight sides 50), 51 and axially restrained by the dowel pins 52, 53, 54, and 55.

In all instances FIGURES 3, 4, and 5 motion of the control surface 45 to the left causes rotation of the blade 42 and spindle 41, by causing the drive nut 44 to move in an outward direction against the long lead threads. Thus, axial motion of the control surface 45 controls the motion of the blades collectively, that is, all blades simultaneously assume equal pit-ch angles.

FIGURE 9 is a cross-sectional view of a submarine hull 70 having therein a pressure hull 71 consisting of a cylindrical portion and spherical end portions and tandem propeller propulsion units consisting of assembly 72, 73, a portion of which is shown in detail in FIG- URE 10.

In FIGURE the pressure hull 71 is shown having a center line 74. A hub 75 circling hull 71 and driven by drive motor 76, rotates about the cylindrical portion of the pressure hull at varying speeds. A U shaped bracket 78 is affixed to hub 75 and has an upper arm 79 and lower arm 80 supporting a spindle 81 having a blade 82 mounted thereon. The longitudinal axis 81a of spindle 81 intersects the longitudinal axis of the pressure hull 74 at an angle 83. This angle is selected so that the upper arm 79 is substantially a smooth continuation of outer hull 70 of the submersible. The only portion of the propeller hub extending beyond the surface of the hull 70 is blade 82 and the connecting portion of spindle 81. Drive nut 84 is confined in a slot (as shown in detail in FIGURE 8 and not reproduced here for clarity) and receives control motion forces from drive surface in a control surface 87.

When a change of pitch is desired for all blades an arm 94 moves to left or right causing an axial sliding nonrotating member 90 to move to the left or right, thus, providing the collective control of the blade angles or pitches through individual drive nuts. An inner eccentric 101 is confined for rotation on a bearing surface 102 of the slide member 90 and an outer eccentric 104 confined for rotation between inner eccentric 101 and control surface arm 87 provides the necessary displacement of surface 87 to cyclically control the pitch of the blades. A somewhat schematic drive is shown for individual eccentrics 101, and 104, including inner eccentric motor 110 and gear coupling 111 for controlling the inner eccentric 101; outer eccentric motor 112 and outer eccentric gear coupling 113 are provided to control the outer eccentric 104. Annular plate 115 provides the necessary rigidity for the eccentric rotation. Control means 120 inside the pressure hull is coupled to motors 110, 112 (by means not shown) to control the position of the eccentrics.

FIGURE 11 shows eccentrics 101 and 104 and control surface 87. It is obvious that the eccentricity of the circular outer surface of 104 with respect to the vessel axis 74 (or outer hull 71) may be varied both in magnitude and orientation by suitably rotating 101 and 104 an appropriate amount and holding them fixed, Control surface 87 then rotates with the hub about the outer surface of 104 thereby having a fixed eccentricity giving a cyclic pitch variations to the blades as they rotate about the hull. It can be seen that 101 and 104 are only rotated with respect to the hull incidental to changing the cyclic pitch amplitude and orientation.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

I claim:

1. A submarine vehicle for operation in a fiuid medium, comprising:

(a) an outer hull of general spheroid shape having an axis of generation;

(b) an inner pressure hull within said outer hull having a longitudinal axis generally coinciding with said axis of generation;

(c) first and second rotatable hubs on said inner hull having portions designed to be smooth continuations of said outer hull;

(d) a plurality of spindles on said first and second hubs having axes normal to said smooth continuation of said outer hull;

(e) blades individually mounted on said spindles; and

(f) means, including a plurality of control arms individually controlling the rotation of said individual spindles, individually and collectively driveable by drive means for collectively and individually controlling the pitch of said blades to provide maneuvering said vehicle independently in six degrees of freedom.

2. A submarine vehicle for operation in a fluid medium, comprising:

(a) an outer hull of general spheroid shape having an axis of generation;

(b) an inner pressure hull within said outer hull having a longitudinal axis generally coinciding with said axis of generation;

(0) first and second rotatable hubs on said inner hull having portions designed to be smooth continuations of said outer hull, said hubs counter-rotating with respect to each other;

,(d) a plurality of rotatable spindles on said first and second hubs axes normal to said smooth continuation of said outer hull, said spindle axes intersecting said axis of generation at an acute angle;

(e) blades individually mounted on said spindles; and

(f) means, including a plurality of control arms individually controlling the rotation of said individual spindles, individually and collectively driveable by drive means for collectively and individually controlling the pitch of said blades to provide maneuvering said vehicle independently in six degrees of freedom.

3. A submarine vehicle for operation in a fluid medium, comprising:

(a) an outer hull of general spheroid shape having an axis of generation;

(b) an inner pressure hull within said outer hull having a longitudinal axis generally coinciding with said axis of generation;

(c) first and second rotatable hubs on said inner hull having portions designed to be smooth continuations of said outer hull;

(d) a plurality of spindles on said first and second hubs having axes normal to said smooth continuation of said outer hull;

(e) blades individually mounted on said spindles;

(f) a plurality of control arms individually coupling said spindles, said control arms joined in an annular ring;

(g) slideable means associated with each hub, slideable upon said inner hull;

(h) a first eccentric rotatable about said slideable member;

(i) a second eccentric rotatably mounted on said first eccentric and having said control ring mounted thereon;

(j) means, for positioning said slideable member along said axis of generation for collectively controlling the pitch of said blades; and

(k) means for rotating said eccentrics to individually control the pitch of individual blades.

4. A tandem propeller, comprising:

(a) an inner hub rotatable about an axis;

(b) a U shaped portion mounted about said inner hub;

(c) a plurality of spindles supported by said U shaped member for rotation about their individual longitudinal axis, said spindles individually having threaded portions thereon for driving said spindles in rotation about their individual axis;

((1) a plurality of nuts individually encompassing said spindles and having threaded portions engageably coupled with said threaded portions of said spindles for driving said spindles;

(e) a blade mounted on each of said spindle having its pitch controlled by rotation of said spindle;

f) a GOI tIQI arm engaging each of said nuts; and

(g) means for moving said nut along the axis of said spindle for rotatably positioning said blades to have a predetermined angle with respect to the rotation of said hub.

5. The tandem propeller of claim 4 wherein said moving means includes first and second eccentrics individually rotatable about said moving means.

6. The tandem propeller of claim 4 wherein said moving means includes a first eccentric rotatable about said moving means and a second eccentric rotatable about said first eccentric.

7. The tandem propeller of claim 5 wherein a shroud means are provided mounted about said blades wherein said shroud has a longitudinal axis which is normal to spindle axis.

References Cited by the Examiner UNITED STATES PATENTS Reilley 1152O X Combs 114-16 Hoke, Ir. 114l6 X Haselton 114-16 MILTON BUCHLER, Primary Examiner.

15 T. M. BLDC, Assistant Examiner. 

1. A SUBMARINE VEHICLE FOR OPERATION IN A FLUID MEDIUM, COMPRISING: (A) AN OUTER HULL OF GENERAL SPHEROID SHAPE HAVING AN AXIS OF GENERATION; (B) AN INNER PRESSURE HULL WITHIN SAID OUTER HULL HAVING A LONGITUDINAL AXIS GENERALLY COINCIDING WITH SAID AXIS OF GENERATION; (C) FIRST AND SECOND ROTATABLE HUBS ON SAID INNER HULL HAVING PORTIONS DESIGNED TO BE SMOOTH CONTINUATIONS OF SAID OUTER HULL; (D) A PLURALITY OF SPINDLES ON SAID FIRST AND SECOND HUBS HAVING AXES NORMAL TO SAID SMOOTH CONTINUATION OF SAID OUTER HULL; (E) BLADES INDIVIDUALLY MOUNTED ON SAID SPINDLES; AND 